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    <meta charset="UTF-8">
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    <title>Document</title>
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    <script>
        //传统方式定义一个函数
        var f1 = function(a) {
            return a;
        }
        console.log(f1(3));


        // es6箭头函数定义
        //参数=>函数体
        var f2 = a => a;
        console.log(f2(4))


        var f3 = function(m, n) {
            return m + n;
        }

        var f4 = (m, n) => m + n;
    </script>
</body>

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